package thread;

public class SyncDemo {
    static boolean success1;
    static boolean success2;


    public static void main(String[] args) {
        Bank bank = new Bank();
        int sum = 1;
        while (true) {
            Thread t1 = new Thread() {
                public void run() {
                    success1 = bank.getMoney(20000);
                }
            };
            Thread t2 = new Thread() {
                public void run() {
                    success2 = bank.getMoney(20000);
                }
            };

            t1.start();
            t2.start();
            try {
                Thread.sleep(50);
            } catch (InterruptedException e) {
            }
            if (success1 && success2) {
                System.out.println("成功取钱");
                System.out.println("一共尝试了" + sum + "次");
                break;
            } else {
                bank.saveAccount(20000);
                sum++;
                success1 = false;
                success2 = false;
            }
        }
    }
}

            class Bank {
                private int account = 1000;

                public synchronized boolean getMoney(int money) {
                    int account = getAccount();
                    if (account >= money) {
                        account = account - money;
                        Thread.yield();
                        saveAccount(account);
                        return true;
                    }
                    return false;
                }

                public void saveAccount(int account) {
                    this.account = account;
                }

                public int getAccount() {
                    return account;
                }
            }

